This type of device is used in order to limit torque mechanically, e.g. in drive shafts or similar structural parts next to clutches with break bolts, slide clutches, clutches with radial serrations, and others. The clutch used on which the invention is based is commonly employed as a shaft coupling, with the lugs surrounded by so-called carrier links extending in a radial direction. This is not the ideal solution for direct use in larger machine combinations as it requires two axially aligned stubs.
The present invention is an overload control device of the type mentioned initially arranged so as to make it usable for machinery which do not have opposing shaft ends. One machine part is a shaft, and the cooperating machine part is a concentric hub, so that the lugs may be arranged at the faces of the machine parts, extending axially. Thus, a control device is provided which, while using the advantages of the familiar device, is well suited to protect machinery with construction which does not permit the use of shaft couplings. Preferably three lugs, uniformly distributed over the circumference, are provided which are surrounded by hollow cylindrical carrier links or rings.
Another detail of the invention is that the lugs and, if applicable, at least a portion of the adjacent link stripper, or scraping surfaces of the machine parts are separate and replaceable. This results in an easy interchangeability of parts damaged, should this be the case, as well as simplified manufacture of the replacement parts.
According to a very favorable feature of the invention, provision is made to arrange, between the machine shaft and the machine hub, a concentric ring, centrally divided in a peripheral direction. The concentrically divided ring halves are provided with serrations at the outer and inner circumference thereof for engaging with the corresponding serrations in the machine parts. The divided ring, on both sides of the central division thereof, has one each of the two substantially semi-cylindrical lug halves. This allows for a favorable interchangeability of the parts representing the overload control. The manufacture of the overload control, and subsequent installation into existing parts is, therefore, made simple. The centrally divided ring is kept in place by means of supports attached to end faces of the machine parts, and overlapping the end faces of the divided ring. These supports prevent the ring from falling from the machine part.
In order to make it easier to install the substantially semi-cylindrical lugs in the proper position after having disconnected the overload control, the invention provides for inserting into the partition line of the divided ring spring biased cylinders which lock into corresponding recesses. Preferably, the number of cylinders matches the number of hollow cylindrical carrier links.